You are aware what $? means, yes? It's a return code. It is not a mathematical result, but it is the result of the expression.
The result of the expression (( X = 0 )) is zero, which considered as a boolean means false, which as a return code means failure, so $? becomes 1.
The result of (( X = 1 )) is nonzero, which considered as a boolean means true, which as a return code means success, so $? becomes 0.
It does this because this is how mathematical functions work in most languages, which is what (( )) is for. If you don't want to do that, there's the old fashioned way.
Friends,
I have a file with contents like:
interface Serial0/4/0/0/1/1/1/1:0
encapsulation mfr
multilink
group 101
Now I need to manipulate the file in such a way that to all the numbers less than 163, 63 gets added and to all numbers greater than 163, 63 gets deducted.(The numbers... (2 Replies)
Hello, I'm relatively new to using bc so I could use some help. In this script im working on I want to have the bc function to calculate float numbers for imagemagicks convert charcoal. Below is what I'm talking about. There are no syntax errors but when it outputs the users frames for example 0-10... (2 Replies)
I use the following shell script in bash and it works fine. It returns 1
# cat /etc/httpd/conf/res.txt
maldet(24444): {scan} scan completed on eicar_com.zip: files 1, malware hits 1, cleaned hits 0
# if ]; then echo 0 > /etc/httpd/conf/malflag; else echo 1 > /etc/httpd/conf/malflag;... (2 Replies)
ls -l /md01/EL/MarketData/inbound/ststr/INVENTORY* |tail -5 |awk '{ print $5,$6,$7,$8,$9 }'If I run the above from the command line the output to md_email is formatted correctly as
78213497 May 1 12:50 /md01/EL/MarketData/inbound/ststr/INVENTORY.20120430.PINESTREET.CSV.done
77904740 May 2... (3 Replies)
I have 2 numbers
xmin = 0.369000018
xmax = 0.569000006
and want to calculate
(xmax- xmin) / 5.0
I have tried using $(( )) but is always giving an error (8 Replies)
Hi,
I have the following code which is giving error mentioned below. Please can you support on this. Also suggest how can we access all the items against single vasservicename in circlename array,i.e, vasservicename say MTSTV will be available to all circles which are mentioned in the array... (2 Replies)
I am using bash
I have a script that takes a number, i.e. 85.152, which is always a non integer and essentially tries to get that number to be a multiple of 10. My code is as follows:
number=85.152
A=${number%.*} #Converts float to integer
typeset -i B=$(((A-20)/10)) #subtracting 20 is... (12 Replies)
Hello everyone,
I need help comparing 2 arrays. the first array is static; the second array is not ..
array1=( "macOS Mojave" "iTunes" )
cd /Volumes
array2=( * )
# output of array2
macOS Mojave
iTunes
Mac me
The problem occurs when I compare the arrays with the following code -
... (6 Replies)
I need to divide the number of white spaces by total number of characters in a file using bash. I am able to get the number of white spaces correctly using:
tr -cd < afile | wc -c
I am also able to get the total number of characters using:
wc -c afile
How do I divide the first... (2 Replies)
Discussion started by: ngabrani
2 Replies
LEARN ABOUT OPENDARWIN
tcl_exprdouble
Tcl_ExprLong(3) Tcl Library Procedures Tcl_ExprLong(3)__________________________________________________________________________________________________________________________________________________NAME
Tcl_ExprLong, Tcl_ExprDouble, Tcl_ExprBoolean, Tcl_ExprString - evaluate an expression
SYNOPSIS
#include <tcl.h>
int
Tcl_ExprLong(interp, string, longPtr)
int
Tcl_ExprDouble(interp, string, doublePtr)
int
Tcl_ExprBoolean(interp, string, booleanPtr)
int
Tcl_ExprString(interp, string)
ARGUMENTS
Tcl_Interp *interp (in) Interpreter in whose context to evaluate string or objPtr. |
CONST char *string (in) |
Expression to be evaluated.
long *longPtr (out) Pointer to location in which to store the integer value of the expression.
int *doublePtr (out) Pointer to location in which to store the floating-point value of the expression.
int *booleanPtr (out) Pointer to location in which to store the 0/1 boolean value of the expression.
_________________________________________________________________DESCRIPTION
These four procedures all evaluate the expression given by the string argument and return the result in one of four different forms. The
expression can have any of the forms accepted by the expr command. Note that these procedures have been largely replaced by the object-
based procedures Tcl_ExprLongObj, Tcl_ExprDoubleObj, Tcl_ExprBooleanObj, and Tcl_ExprObj. Those object-based procedures evaluate an
expression held in a Tcl object instead of a string. The object argument can retain an internal representation that is more efficient to
execute.
The interp argument refers to an interpreter used to evaluate the expression (e.g. for variables and nested Tcl commands) and to return
error information.
For all of these procedures the return value is a standard Tcl result: TCL_OK means the expression was successfully evaluated, and
TCL_ERROR means that an error occurred while evaluating the expression. If TCL_ERROR is returned then the interpreter's result will hold a
message describing the error. If an error occurs while executing a Tcl command embedded in the expression then that error will be
returned.
If the expression is successfully evaluated, then its value is returned in one of four forms, depending on which procedure is invoked.
Tcl_ExprLong stores an integer value at *longPtr. If the expression's actual value is a floating-point number, then it is truncated to an
integer. If the expression's actual value is a non-numeric string then an error is returned.
Tcl_ExprDouble stores a floating-point value at *doublePtr. If the expression's actual value is an integer, it is converted to floating-
point. If the expression's actual value is a non-numeric string then an error is returned.
Tcl_ExprBoolean stores a 0/1 integer value at *booleanPtr. If the expression's actual value is an integer or floating-point number, then
they store 0 at *booleanPtr if the value was zero and 1 otherwise. If the expression's actual value is a non-numeric string then it must
be one of the values accepted by Tcl_GetBoolean such as ``yes'' or ``no'', or else an error occurs.
Tcl_ExprString returns the value of the expression as a string stored in the interpreter's result. If the expression's actual value is an
integer then Tcl_ExprString converts it to a string using sprintf with a ``%d'' converter. If the expression's actual value is a floating-
point number, then Tcl_ExprString calls Tcl_PrintDouble to convert it to a string.
SEE ALSO
Tcl_ExprLongObj, Tcl_ExprDoubleObj, Tcl_ExprBooleanObj, Tcl_ExprObj
KEYWORDS
boolean, double, evaluate, expression, integer, object, string
Tcl 7.0 Tcl_ExprLong(3)